Wednesday, May 12, 2010

Morneau's Monster Start

Justin Morneau has always been a fast starter, especially compared to his well-documented woes in August and September. His overall slash line for March and April is .297/.376/.544, and for May it's even better at .308/.385/.477, and as a frame of reference, his line for August is .250/.327/.443.

This season, however, he's outdoing himself. Morneau has been an absolute beast so far this year, and although he isn't putting up gaudy numbers in the the traditional power stats (8 HR, 23 RBI), there are plenty of other stats that give a great picture of how valuable he's been this year. Let's take a look at how he stacks up to the rest of the league so far.

AVG: .348, 5th in AL.
OBP: .479, 1st in AL.
SLG: .652, 2nd in AL.
BB/K ratio: 1.17, 6th in AL.
wOBA: .480, 1st in AL.

That last stat is something I'd like to highlight. wOBA stands for "weighted on-base average" and is available at FanGraphs. The gist of how it works is something like this. OBP tells us in simple terms how often a player reaches base in relation to his total number of plate appearances, but it doesn't tell us how they reached (walks, singles, doubles, triples and home runs all receive equal consideration). Slugging percentage does tell us the types of hits a player gets and gives extra-base hits more value, but it excludes walks. wOBA aims to combine these two concepts into a meaningful stat that goes beyond the now-mainstream OPS, which simply adds OBP and SLG together.

wOBA assigns each type of hit a value in terms of the average number of runs it creates (with an out being zero), which sabermetrician Tom Tango derived from a whole bunch of historical number-crunching that would probably make my head explode if I thought about it too much. Home runs are worth the most at 1.7 runs above an out (this obviously takes into account multi-run homers), and on down the list. When these values are applied to a league-average hitter and the result is divided by the number of plate appearances, it comes out right around .300, which would be fine if that was a number we could understand.

Conveniently, it so happens that adding 15% to .300 is the league-average OBP, so once you add 15% to the weights listed above, you have a number that tracks quite nicely along the OBP scale (.300 is brutal, .400 is the cream of the crop, etc). Tango explains it in a little more depth here. The bottom line is that what you're left with is a number that's easily interpreted along a scale we all understand, but that takes into account the differing values of what a hitter does with his plate appearances.

wOBA is a pretty good picture of a hitter's overall offensive contribution, and it's certainly nice to have a player on your team who ranks second in all of baseball (behind only Ethier, who AK discussed yesterday). Like Ethier, Morneau's torrid pace isn't going to be sustainable over the course of the season, but a big part of his spike in OBP (and thus, by extension wOBA) is due to increased plate discipline, and that is certainly sustainable. Morneau's walk rate has gone up every year since 2006, a increase that has gone hand-in-hand with a decrease in the percentage of balls he swings at outside the strike zone. He's gotten an MLB-leading 28 free passes thus far, and seems to be more content to wait for "his pitch", as his overall swing percentage is also at an all-time career low.

Like I said, he won't be able to keep this up all season, and his average is being aided somewhat by a .388 BABIP, but Morneau has started hotter than he's ever started. Obviously it's still early, and I'm going to stay away from the term "career year," but with a newfound patience at the plate and a Twins lineup surrounding him that's appearing as potent as it's ever been, there's no reason not to think that this couldn't be one of his most valuable seasons.

1 comment:

  1. I was gonna attempt a "say it ain't so" argument in regards to Morneau's BABIP so far by looking up his year-by-year avg in that category, but the stats don't help me .291 BABIP. HOWEVER, he did post a .328 BABIP in his MVP season and a .312 in 2008.